Friction devices, or so called “drag systems” have been designed into fishing reels for many decades, if not more than a century. Some of the earliest reels utilized an educated thumb or finger pressed against the spinning spool of line to create friction, thus slowing down a fish that was hooked and running away. Early on in the evolution of fishing reels, mechanical devices were introduced which accomplished this same objective in a less subjective and, sometimes, less painful manner. The numbers of systems and the way they functioned are essentially countless.
Regardless, a fishing reel drag typically requires three essential elements in functional interaction. First, it must have a drag adjustment knob which can be grasped and tightened to apply pressure to the drag mechanism. This is typically a threaded knob tightening on the end of a threaded shaft onto which the drag mechanism is spindled. The drag mechanism itself is another essential element and typically consists of various types of materials in resistive or frictional contact. The third important element is the drag adjustment spring which moderates the tightening effect of the drag knob on the drag mechanism. The spring allows pressure to be applied to the drag mechanism more gradually and evenly, thus creating friction more gradually than would be possible with just the threaded drag knob itself.
Line is then removed from a spinning reel spool by a fleeing fish against the friction created by this drag system. The friction created has to be sufficient to slow the fish, thus tiring it, and yet not become so great as to cause the line to break. Typically, a desirable setting for a drag system on a spinning reel is no more than 25% to 30% of the breaking strength of the line.
Due to the counter-intuitive nature of the laws of friction, most of the drag systems that have been created to date probably do not function in the way their inventor envisioned. While most spinning reel drags are comprised of some version of the three basic elements described above, very little good science has been utilized to date to objectively measure just bow predictably and reliably these various mechanisms really function. For the most part, a successfully landed fish has been considered proof enough that the system was working. But many times fishing adventures have not ended that successfully. When the failure was attributable to the drag mechanism, no one actually knew for sure, and “The big one got away.”
The basic laws of friction for surfaces in dry contact that relate to creating a spinning reel drag system are as follows:
1. The amount of friction created is directly proportional to the normal force (amount of pressure applied) between the surfaces in contact.
2. The amount of friction created by surfaces in frictional contact is independent of the areas in contact so long as the normal force (applied pressure) remains the same.
3. At low velocities (as in spinning reel drags) the friction is independent of the velocity between the surfaces in frictional contact, except that as the velocity increases, the friction decreases. The exception to this is that soft materials such as rubber, leather, cork, and other soft plastics as are used in reel drags do not follow these rules to the letter. These soft materials will to a degree create more friction as the velocity increases, and create more friction as the surface area increases. The degree of change from the standard rules varies greatly depending on the material in question.
The basic laws of friction for lubricated surfaces are much different and some very complicated results can occur:
1. The amount of friction created is almost independent of the normal force (pressure applied) acting upon the surfaces.
2. The amount of friction for well lubricated surfaces depends to a great extent on the temperature of the surfaces.
3. If the contact surfaces are flooded with oil (as many reel drags are), the amount of friction is almost independent of the nature of the surfaces until the lubrication becomes less ample and then the friction becomes more dependent on the nature of the materials in contact. What this means for the angler and reel drag designer is that lubricated drag systems may never perform predictably, reliably, or consistently. Even placing a fishing reel on the deck of a boat exposed to hot tropical sun can change its performance drastically before the first cast is made.
In fact, little consideration has been given in prior art to the problems created by the combination of pressure and heat on the drag mechanism surfaces in frictional contact, indeed to how the laws of friction operate in general concerning spinning reel drag systems. As frictional drag mechanisms generate heat, thermal expansion of the drag mechanism materials may create profound changes in the drag systems performance, essentially causing an increase in drag forces much the same as would be accomplished by further tightening the drag knob, thus creating more pressure on the drag adjustment spring and more pressure on the drag mechanism. Also, with heat and pressure, many of the commonly used drag system materials are known to go through changes at their contact surfaces which can cause the drag forces to fade, thus drag performance is diminished. The prior art has given little consideration to these problems. No viable solutions have been offered which might combine drag materials, or create better heat sinks to absorb the generated heat, making for more reliable performance.
Many different types of materials, compression springs, and drag adjustment knobs have been conjoined to create what was believed by its creator to be the ultimate spinning reel drag. “Smooth” has always been the catch word used to describe how well the drag friction system would allow line to be removed from the spool during a fish fight. Unfortunately, little other science has been used to clearly establish the performance characteristics of these ultimate drags. And while many drag systems are smooth when line is pulled from the spool by hand, what actually happens beyond that point with a fish on and line screaming from the reel has never been clearly described prior to the present invention.
In summary, it is apparent that a spinning reel drag system is needed that will perform beyond what “feels good to the hand.” A system of drag washers is needed with qualities that will interact with an adequate heat sink to create a so called “flat running drag.” A flat running drag is a drag performance characteristic in which the amount of drag force created by a running spool does not vary from the time the line begins to flow from the spool, until the line on the spool is exhausted.
What is further needed is a spinning reel drag system that does not utilize oils or grease, and is virtually maintenance free requiring only an occasional wipe from a dry cloth to keep the drag system operating exactly the same from fish to fish and from outing to outing.